progs/demos/drawpix.c

   1 /* $Id: drawpix.c,v 1.6 2002/01/26 17:49:30 brianp Exp $ */
   2
   3 /*
   4  * glDrawPixels demo/test/benchmark
   5  *
   6  * Brian Paul   September 25, 1997  This file is in the public domain.
   7  */
   8
   9 /*
  10  * $Log: drawpix.c,v $
  11  * Revision 1.6  2002/01/26 17:49:30  brianp
  12  * added fog and raster Z position controls
  13  *
  14  * Revision 1.5  2000/12/24 22:53:54  pesco
  15  * * demos/Makefile.am (INCLUDES): Added -I$(top_srcdir)/util.
  16  * * demos/Makefile.X11, demos/Makefile.BeOS-R4, demos/Makefile.cygnus:
  17  * Essentially the same.
  18  * Program files updated to include "readtex.c", not "../util/readtex.c".
  19  * * demos/reflect.c: Likewise for "showbuffer.c".
  20  *
  21  *
  22  * * Makefile.am (EXTRA_DIST): Added top-level regular files.
  23  *
  24  * * include/GL/Makefile.am (INC_X11): Added glxext.h.
  25  *
  26  *
  27  * * src/GGI/include/ggi/mesa/Makefile.am (EXTRA_HEADERS): Include
  28  * Mesa GGI headers in dist even if HAVE_GGI is not given.
  29  *
  30  * * configure.in: Look for GLUT and demo source dirs in $srcdir.
  31  *
  32  * * src/swrast/Makefile.am (libMesaSwrast_la_SOURCES): Set to *.[ch].
  33  * More source list updates in various Makefile.am's.
  34  *
  35  * * Makefile.am (dist-hook): Remove CVS directory from distribution.
  36  * (DIST_SUBDIRS): List all possible subdirs here.
  37  * (SUBDIRS): Only list subdirs selected for build again.
  38  * The above two applied to all subdir Makefile.am's also.
  39  *
  40  * Revision 1.4  2000/09/08 21:45:21  brianp
  41  * added dither key option
  42  *
  43  * Revision 1.3  1999/10/28 18:23:29  brianp
  44  * minor changes to Usage() function
  45  *
  46  * Revision 1.2  1999/10/21 22:13:58  brianp
  47  * added f key to toggle front/back drawing
  48  *
  49  * Revision 1.1.1.1  1999/08/19 00:55:40  jtg
  50  * Imported sources
  51  *
  52  * Revision 3.3  1999/03/28 18:18:33  brianp
  53  * minor clean-up
  54  *
  55  * Revision 3.2  1998/11/05 04:34:04  brianp
  56  * moved image files to ../images/ directory
  57  *
  58  * Revision 3.1  1998/02/22 16:43:17  brianp
  59  * added a few casts to silence compiler warnings
  60  *
  61  * Revision 3.0  1998/02/14 18:42:29  brianp
  62  * initial rev
  63  *
  64  */
  65
  66
  67 #include <stdio.h>
  68 #include <stdlib.h>
  69 #include <math.h>
  70 #include <GL/glut.h>
  71
  72 #include "readtex.c"
  73
  74 #define IMAGE_FILE "../images/girl.rgb"
  75
  76 static int ImgWidth, ImgHeight;
  77 static GLenum ImgFormat;
  78 static GLubyte *Image = NULL;
  79
  80 static int Xpos, Ypos;
  81 static int SkipPixels, SkipRows;
  82 static int DrawWidth, DrawHeight;
  83 static int Scissor = 0;
  84 static int Fog = 0;
  85 static GLfloat Zpos = -1.0;
  86 static float Xzoom, Yzoom;
  87 static GLboolean DrawFront = GL_FALSE;
  88 static GLboolean Dither = GL_TRUE;
  89
  90
  91 static void Reset( void )
  92 {
  93    Xpos = Ypos = 20;
  94    DrawWidth = ImgWidth;
  95    DrawHeight = ImgHeight;
  96    SkipPixels = SkipRows = 0;
  97    Scissor = 0;
  98    Fog = 0;
  99    Zpos = -1.0;
 100    Xzoom = Yzoom = 1.0;
 101 }
 102
 103
 104 static void Display( void )
 105 {
 106    glClear( GL_COLOR_BUFFER_BIT );
 107
 108 #if 0
 109    glRasterPos2i(Xpos, Ypos);
 110 #else
 111    /* This allows negative raster positions: */
 112    glRasterPos3f(0, 0, Zpos);
 113    glBitmap(0, 0, 0, 0, Xpos, Ypos, NULL);
 114 #endif
 115
 116    glPixelStorei(GL_UNPACK_SKIP_PIXELS, SkipPixels);
 117    glPixelStorei(GL_UNPACK_SKIP_ROWS, SkipRows);
 118
 119    glPixelZoom( Xzoom, Yzoom );
 120
 121    if (Scissor)
 122       glEnable(GL_SCISSOR_TEST);
 123
 124    if (Fog)
 125       glEnable(GL_FOG);
 126
 127    glDrawPixels(DrawWidth, DrawHeight, ImgFormat, GL_UNSIGNED_BYTE, Image);
 128
 129    glDisable(GL_SCISSOR_TEST);
 130    glDisable(GL_FOG);
 131
 132    if (!DrawFront)
 133       glutSwapBuffers();
 134 }
 135
 136
 137 static void Benchmark( void )
 138 {
 139    int startTime, endTime;
 140    int draws = 500;
 141    double seconds, pixelsPerSecond;
 142
 143    printf("Benchmarking...\n");
 144    /* GL set-up */
 145    glPixelStorei(GL_UNPACK_SKIP_PIXELS, SkipPixels);
 146    glPixelStorei(GL_UNPACK_SKIP_ROWS, SkipRows);
 147    glPixelZoom( Xzoom, Yzoom );
 148    if (Scissor)
 149       glEnable(GL_SCISSOR_TEST);
 150    if (Fog)
 151       glEnable(GL_FOG);
 152
 153    if (DrawFront)
 154       glDrawBuffer(GL_FRONT);
 155    else
 156       glDrawBuffer(GL_BACK);
 157
 158    /* Run timing test */
 159    draws = 0;
 160    startTime = glutGet(GLUT_ELAPSED_TIME);
 161    do {
 162       glDrawPixels(DrawWidth, DrawHeight, ImgFormat, GL_UNSIGNED_BYTE, Image);
 163       draws++;
 164       endTime = glutGet(GLUT_ELAPSED_TIME);
 165    } while (endTime - startTime < 4000);   /* 4 seconds */
 166
 167    /* GL clean-up */
 168    glDisable(GL_SCISSOR_TEST);
 169    glDisable(GL_FOG);
 170
 171    /* Results */
 172    seconds = (double) (endTime - startTime) / 1000.0;
 173    pixelsPerSecond = draws * DrawWidth * DrawHeight / seconds;
 174    printf("Result:  %d draws in %f seconds = %f pixels/sec\n",
 175           draws, seconds, pixelsPerSecond);
 176 }
 177
 178
 179 static void Reshape( int width, int height )
 180 {
 181    glViewport( 0, 0, width, height );
 182    glMatrixMode( GL_PROJECTION );
 183    glLoadIdentity();
 184    glOrtho( 0.0, width, 0.0, height, 0.0, 2.0 );
 185    glMatrixMode( GL_MODELVIEW );
 186    glLoadIdentity();
 187
 188    glScissor(width/4, height/4, width/2, height/2);
 189 }
 190
 191
 192 static void Key( unsigned char key, int x, int y )
 193 {
 194    (void) x;
 195    (void) y;
 196    switch (key) {
 197       case ' ':
 198          Reset();
 199          break;
 200       case 'd':
 201          Dither = !Dither;
 202          if (Dither)
 203             glEnable(GL_DITHER);
 204          else
 205             glDisable(GL_DITHER);
 206          break;
 207       case 'w':
 208          if (DrawWidth > 0)
 209             DrawWidth--;
 210          break;
 211       case 'W':
 212          DrawWidth++;
 213          break;
 214       case 'h':
 215          if (DrawHeight > 0)
 216             DrawHeight--;
 217          break;
 218       case 'H':
 219          DrawHeight++;
 220          break;
 221       case 'p':
 222          if (SkipPixels > 0)
 223              SkipPixels--;
 224          break;
 225       case 'P':
 226          SkipPixels++;
 227          break;
 228       case 'r':
 229          if (SkipRows > 0)
 230              SkipRows--;
 231          break;
 232       case 'R':
 233          SkipRows++;
 234          break;
 235       case 's':
 236          Scissor = !Scissor;
 237          break;
 238       case 'x':
 239          Xzoom -= 0.1;
 240          break;
 241       case 'X':
 242          Xzoom += 0.1;
 243          break;
 244       case 'y':
 245          Yzoom -= 0.1;
 246          break;
 247       case 'Y':
 248          Yzoom += 0.1;
 249          break;
 250       case 'z':
 251          Zpos -= 0.1;
 252          printf("RasterPos Z = %g\n", Zpos);
 253          break;
 254       case 'Z':
 255          Zpos += 0.1;
 256          printf("RasterPos Z = %g\n", Zpos);
 257          break;
 258       case 'b':
 259          Benchmark();
 260          break;
 261       case 'F':
 262          Fog = !Fog;
 263          printf("Fog %d\n", Fog);
 264          break;
 265       case 'f':
 266          DrawFront = !DrawFront;
 267          if (DrawFront)
 268             glDrawBuffer(GL_FRONT);
 269          else
 270             glDrawBuffer(GL_BACK);
 271          printf("glDrawBuffer(%s)\n", DrawFront ? "GL_FRONT" : "GL_BACK");
 272          break;
 273       case 27:
 274          exit(0);
 275          break;
 276    }
 277    glutPostRedisplay();
 278 }
 279
 280
 281 static void SpecialKey( int key, int x, int y )
 282 {
 283    (void) x;
 284    (void) y;
 285    switch (key) {
 286       case GLUT_KEY_UP:
 287          Ypos += 1;
 288          break;
 289       case GLUT_KEY_DOWN:
 290          Ypos -= 1;
 291          break;
 292       case GLUT_KEY_LEFT:
 293          Xpos -= 1;
 294          break;
 295       case GLUT_KEY_RIGHT:
 296          Xpos += 1;
 297          break;
 298    }
 299    glutPostRedisplay();
 300 }
 301
 302
 303 static void Init( GLboolean ciMode )
 304 {
 305    static const GLfloat fogColor[4] = {0, 1, 0, 0};
 306
 307    printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
 308    printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
 309
 310    Image = LoadRGBImage( IMAGE_FILE, &ImgWidth, &ImgHeight, &ImgFormat );
 311    if (!Image) {
 312       printf("Couldn't read %s\n", IMAGE_FILE);
 313       exit(0);
 314    }
 315
 316    if (ciMode) {
 317       /* Convert RGB image to grayscale */
 318       GLubyte *indexImage = malloc( ImgWidth * ImgHeight );
 319       GLint i;
 320       for (i=0; i<ImgWidth*ImgHeight; i++) {
 321          int gray = Image[i*3] + Image[i*3+1] + Image[i*3+2];
 322          indexImage[i] = gray / 3;
 323       }
 324       free(Image);
 325       Image = indexImage;
 326       ImgFormat = GL_COLOR_INDEX;
 327
 328       for (i=0;i<255;i++) {
 329          float g = i / 255.0;
 330          glutSetColor(i, g, g, g);
 331       }
 332    }
 333
 334    printf("Loaded %d by %d image\n", ImgWidth, ImgHeight );
 335
 336    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 337    glPixelStorei(GL_UNPACK_ROW_LENGTH, ImgWidth);
 338
 339    glFogi(GL_FOG_MODE, GL_LINEAR);
 340    glFogf(GL_FOG_START, 0);
 341    glFogf(GL_FOG_END, 2);
 342    glFogfv(GL_FOG_COLOR, fogColor);
 343
 344    Reset();
 345 }
 346
 347
 348 static void Usage(void)
 349 {
 350    printf("Keys:\n");
 351    printf("       SPACE  Reset Parameters\n");
 352    printf("     Up/Down  Move image up/down\n");
 353    printf("  Left/Right  Move image left/right\n");
 354    printf("           x  Decrease X-axis PixelZoom\n");
 355    printf("           X  Increase X-axis PixelZoom\n");
 356    printf("           y  Decrease Y-axis PixelZoom\n");
 357    printf("           Y  Increase Y-axis PixelZoom\n");
 358    printf("           w  Decrease glDrawPixels width*\n");
 359    printf("           W  Increase glDrawPixels width*\n");
 360    printf("           h  Decrease glDrawPixels height*\n");
 361    printf("           H  Increase glDrawPixels height*\n");
 362    printf("           p  Decrease GL_UNPACK_SKIP_PIXELS*\n");
 363    printf("           P  Increase GL_UNPACK_SKIP_PIXELS*\n");
 364    printf("           r  Decrease GL_UNPACK_SKIP_ROWS*\n");
 365    printf("           R  Increase GL_UNPACK_SKIP_ROWS*\n");
 366    printf("           s  Toggle GL_SCISSOR_TEST\n");
 367    printf("           F  Toggle GL_FOG\n");
 368    printf("           z  Decrease RasterPos Z\n");
 369    printf("           Z  Increase RasterPos Z\n");
 370
 371    printf("           f  Toggle front/back buffer drawing\n");
 372    printf("           b  Benchmark test\n");
 373    printf("         ESC  Exit\n");
 374    printf("* Warning: no limits are imposed on these parameters so it's\n");
 375    printf("  possible to cause a segfault if you go too far.\n");
 376 }
 377
 378
 379 int main( int argc, char *argv[] )
 380 {
 381    GLboolean ciMode = GL_FALSE;
 382
 383    if (argc > 1 && strcmp(argv[1], "-ci")==0) {
 384       ciMode = GL_TRUE;
 385    }
 386
 387    glutInit( &argc, argv );
 388    glutInitWindowPosition( 0, 0 );
 389    glutInitWindowSize( 500, 400 );
 390
 391    if (ciMode)
 392       glutInitDisplayMode( GLUT_INDEX | GLUT_DOUBLE );
 393    else
 394       glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE);
 395
 396    glutCreateWindow(argv[0]);
 397
 398    Init(ciMode);
 399    Usage();
 400
 401    glutReshapeFunc( Reshape );
 402    glutKeyboardFunc( Key );
 403    glutSpecialFunc( SpecialKey );
 404    glutDisplayFunc( Display );
 405
 406    glutMainLoop();
 407    return 0;
 408 }